I looked at my watch and saw that I had just time to get comfortably to the station and meet him there. I felt that it was of the utmost importance that he should know at once of the new and startling developments in the case.

Evidently, I reflected, Poirot had had no difficulty in finding what he wanted in Paris. The quickness of his return proved that. Very few hours had sufficed. I wondered how he would take the exciting news I had to impart.

The train was some minutes late, and I strolled aimlessly up and down the platform, until it occurred to me that I might pass the time by asking a few questions as to who had left Merlinville by the last train on the evening of the tragedy.

I approached the chief porter, an intelligent looking man, and had little difficulty in persuading him to enter upon the subject. It was a disgrace to the Police, he hotly affirmed, that such brigands of assassins should be allowed to go about unpunished. I hinted that there was some possibility they might have left by the midnight train, but he negatived the idea decidedly. He would have noticed two foreigners—he was sure of it. Only about twenty people had left by the train, and he could not have failed to observe them.

I do not know what put the idea into my head—possibly it was the deep anxiety underlying Marthe Daubreuil’s tones—but I asked suddenly:

“Young M. Renauld—he did not leave by that train, did he?”

“Ah, no, monsieur. To arrive and start off again within half an hour, it would not be amusing, that!”

I stared at the man, the significance of his words almost escaping me. Then I saw. …

“You mean,” I said, my heart beating a little, “that M. Jack Renauld arrived at Merlinville that evening?”

“But yes, monsieur. By the last train arriving the other way, the 11:40.”